On 2019-12-04 07:18, -hh wrote:
Just back from a trip where I had the unplanned experience of my Gitzo carbon fiber
tripod come apart on me.


The failure location is near the top of the tripod, between the top interface plate and
the top of the center column tube.

The (now revealed) bottom of the interface plate is like a plug that slides down inside
the ID of the center column tube. Looks like it was a glue failure. FYI these two parts
are also both keyed. This is intended to carry the torsion forces of screwing down a
ball head so as to minimize forces being imparted on the glue joint itself.

FYI, there's some silver-colored residue "stuff" which apparently was the
original glue/adhesive.

I quickly found this online reference, which a quick read suggests using either
superglue or some epoxies, etc:

https://www.permabond.com/materials_bonded/how-to-bond-carbon-fiber-2/


Suggestions?

Epoxy is my choice. Note that full hardness takes about 24 hours.
(This will be on the epoxy instructions).

Initial setting can be accelerated with heat from a hair dryer (for
example) - but take care if there are parts that may expand and upset
the bonding area.

Use mild clamping force. It's good to do a mock setup to make sure
everything will hold together before mixing the expoxy.


I do know that my next step is to unpack the gear and check to see what material
the interface plate's "plug" is made out of; don't believe it to be carbon fiber as
it appears machined ... but black in color: I suspect it is anodized aluminum?

Similarly, what solvents to use to clean the surfaces will also need checking as well.

Isopropyl alcohol to clean parts before using epoxy. Let dry completely.

Dishsoap to clean expoxy messes before it sets (minutes).

I usually mix epoxy on a sheet of aluminum paper with a toothpick.

A later trick I use is the tops of jars. Then after the waste epoxy
sets the jar top is still available for later jobs.